v4.19.13 snapshot.
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
new file mode 100644
index 0000000..8c15c59
--- /dev/null
+++ b/drivers/iommu/iommu.c
@@ -0,0 +1,2016 @@
+/*
+ * Copyright (C) 2007-2008 Advanced Micro Devices, Inc.
+ * Author: Joerg Roedel <jroedel@suse.de>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#define pr_fmt(fmt) "iommu: " fmt
+
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/bug.h>
+#include <linux/types.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/errno.h>
+#include <linux/iommu.h>
+#include <linux/idr.h>
+#include <linux/notifier.h>
+#include <linux/err.h>
+#include <linux/pci.h>
+#include <linux/bitops.h>
+#include <linux/property.h>
+#include <trace/events/iommu.h>
+
+static struct kset *iommu_group_kset;
+static DEFINE_IDA(iommu_group_ida);
+#ifdef CONFIG_IOMMU_DEFAULT_PASSTHROUGH
+static unsigned int iommu_def_domain_type = IOMMU_DOMAIN_IDENTITY;
+#else
+static unsigned int iommu_def_domain_type = IOMMU_DOMAIN_DMA;
+#endif
+
+struct iommu_callback_data {
+ const struct iommu_ops *ops;
+};
+
+struct iommu_group {
+ struct kobject kobj;
+ struct kobject *devices_kobj;
+ struct list_head devices;
+ struct mutex mutex;
+ struct blocking_notifier_head notifier;
+ void *iommu_data;
+ void (*iommu_data_release)(void *iommu_data);
+ char *name;
+ int id;
+ struct iommu_domain *default_domain;
+ struct iommu_domain *domain;
+};
+
+struct group_device {
+ struct list_head list;
+ struct device *dev;
+ char *name;
+};
+
+struct iommu_group_attribute {
+ struct attribute attr;
+ ssize_t (*show)(struct iommu_group *group, char *buf);
+ ssize_t (*store)(struct iommu_group *group,
+ const char *buf, size_t count);
+};
+
+static const char * const iommu_group_resv_type_string[] = {
+ [IOMMU_RESV_DIRECT] = "direct",
+ [IOMMU_RESV_RESERVED] = "reserved",
+ [IOMMU_RESV_MSI] = "msi",
+ [IOMMU_RESV_SW_MSI] = "msi",
+};
+
+#define IOMMU_GROUP_ATTR(_name, _mode, _show, _store) \
+struct iommu_group_attribute iommu_group_attr_##_name = \
+ __ATTR(_name, _mode, _show, _store)
+
+#define to_iommu_group_attr(_attr) \
+ container_of(_attr, struct iommu_group_attribute, attr)
+#define to_iommu_group(_kobj) \
+ container_of(_kobj, struct iommu_group, kobj)
+
+static LIST_HEAD(iommu_device_list);
+static DEFINE_SPINLOCK(iommu_device_lock);
+
+int iommu_device_register(struct iommu_device *iommu)
+{
+ spin_lock(&iommu_device_lock);
+ list_add_tail(&iommu->list, &iommu_device_list);
+ spin_unlock(&iommu_device_lock);
+
+ return 0;
+}
+
+void iommu_device_unregister(struct iommu_device *iommu)
+{
+ spin_lock(&iommu_device_lock);
+ list_del(&iommu->list);
+ spin_unlock(&iommu_device_lock);
+}
+
+static struct iommu_domain *__iommu_domain_alloc(struct bus_type *bus,
+ unsigned type);
+static int __iommu_attach_device(struct iommu_domain *domain,
+ struct device *dev);
+static int __iommu_attach_group(struct iommu_domain *domain,
+ struct iommu_group *group);
+static void __iommu_detach_group(struct iommu_domain *domain,
+ struct iommu_group *group);
+
+static int __init iommu_set_def_domain_type(char *str)
+{
+ bool pt;
+ int ret;
+
+ ret = kstrtobool(str, &pt);
+ if (ret)
+ return ret;
+
+ iommu_def_domain_type = pt ? IOMMU_DOMAIN_IDENTITY : IOMMU_DOMAIN_DMA;
+ return 0;
+}
+early_param("iommu.passthrough", iommu_set_def_domain_type);
+
+static ssize_t iommu_group_attr_show(struct kobject *kobj,
+ struct attribute *__attr, char *buf)
+{
+ struct iommu_group_attribute *attr = to_iommu_group_attr(__attr);
+ struct iommu_group *group = to_iommu_group(kobj);
+ ssize_t ret = -EIO;
+
+ if (attr->show)
+ ret = attr->show(group, buf);
+ return ret;
+}
+
+static ssize_t iommu_group_attr_store(struct kobject *kobj,
+ struct attribute *__attr,
+ const char *buf, size_t count)
+{
+ struct iommu_group_attribute *attr = to_iommu_group_attr(__attr);
+ struct iommu_group *group = to_iommu_group(kobj);
+ ssize_t ret = -EIO;
+
+ if (attr->store)
+ ret = attr->store(group, buf, count);
+ return ret;
+}
+
+static const struct sysfs_ops iommu_group_sysfs_ops = {
+ .show = iommu_group_attr_show,
+ .store = iommu_group_attr_store,
+};
+
+static int iommu_group_create_file(struct iommu_group *group,
+ struct iommu_group_attribute *attr)
+{
+ return sysfs_create_file(&group->kobj, &attr->attr);
+}
+
+static void iommu_group_remove_file(struct iommu_group *group,
+ struct iommu_group_attribute *attr)
+{
+ sysfs_remove_file(&group->kobj, &attr->attr);
+}
+
+static ssize_t iommu_group_show_name(struct iommu_group *group, char *buf)
+{
+ return sprintf(buf, "%s\n", group->name);
+}
+
+/**
+ * iommu_insert_resv_region - Insert a new region in the
+ * list of reserved regions.
+ * @new: new region to insert
+ * @regions: list of regions
+ *
+ * The new element is sorted by address with respect to the other
+ * regions of the same type. In case it overlaps with another
+ * region of the same type, regions are merged. In case it
+ * overlaps with another region of different type, regions are
+ * not merged.
+ */
+static int iommu_insert_resv_region(struct iommu_resv_region *new,
+ struct list_head *regions)
+{
+ struct iommu_resv_region *region;
+ phys_addr_t start = new->start;
+ phys_addr_t end = new->start + new->length - 1;
+ struct list_head *pos = regions->next;
+
+ while (pos != regions) {
+ struct iommu_resv_region *entry =
+ list_entry(pos, struct iommu_resv_region, list);
+ phys_addr_t a = entry->start;
+ phys_addr_t b = entry->start + entry->length - 1;
+ int type = entry->type;
+
+ if (end < a) {
+ goto insert;
+ } else if (start > b) {
+ pos = pos->next;
+ } else if ((start >= a) && (end <= b)) {
+ if (new->type == type)
+ goto done;
+ else
+ pos = pos->next;
+ } else {
+ if (new->type == type) {
+ phys_addr_t new_start = min(a, start);
+ phys_addr_t new_end = max(b, end);
+
+ list_del(&entry->list);
+ entry->start = new_start;
+ entry->length = new_end - new_start + 1;
+ iommu_insert_resv_region(entry, regions);
+ } else {
+ pos = pos->next;
+ }
+ }
+ }
+insert:
+ region = iommu_alloc_resv_region(new->start, new->length,
+ new->prot, new->type);
+ if (!region)
+ return -ENOMEM;
+
+ list_add_tail(®ion->list, pos);
+done:
+ return 0;
+}
+
+static int
+iommu_insert_device_resv_regions(struct list_head *dev_resv_regions,
+ struct list_head *group_resv_regions)
+{
+ struct iommu_resv_region *entry;
+ int ret = 0;
+
+ list_for_each_entry(entry, dev_resv_regions, list) {
+ ret = iommu_insert_resv_region(entry, group_resv_regions);
+ if (ret)
+ break;
+ }
+ return ret;
+}
+
+int iommu_get_group_resv_regions(struct iommu_group *group,
+ struct list_head *head)
+{
+ struct group_device *device;
+ int ret = 0;
+
+ mutex_lock(&group->mutex);
+ list_for_each_entry(device, &group->devices, list) {
+ struct list_head dev_resv_regions;
+
+ INIT_LIST_HEAD(&dev_resv_regions);
+ iommu_get_resv_regions(device->dev, &dev_resv_regions);
+ ret = iommu_insert_device_resv_regions(&dev_resv_regions, head);
+ iommu_put_resv_regions(device->dev, &dev_resv_regions);
+ if (ret)
+ break;
+ }
+ mutex_unlock(&group->mutex);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iommu_get_group_resv_regions);
+
+static ssize_t iommu_group_show_resv_regions(struct iommu_group *group,
+ char *buf)
+{
+ struct iommu_resv_region *region, *next;
+ struct list_head group_resv_regions;
+ char *str = buf;
+
+ INIT_LIST_HEAD(&group_resv_regions);
+ iommu_get_group_resv_regions(group, &group_resv_regions);
+
+ list_for_each_entry_safe(region, next, &group_resv_regions, list) {
+ str += sprintf(str, "0x%016llx 0x%016llx %s\n",
+ (long long int)region->start,
+ (long long int)(region->start +
+ region->length - 1),
+ iommu_group_resv_type_string[region->type]);
+ kfree(region);
+ }
+
+ return (str - buf);
+}
+
+static ssize_t iommu_group_show_type(struct iommu_group *group,
+ char *buf)
+{
+ char *type = "unknown\n";
+
+ if (group->default_domain) {
+ switch (group->default_domain->type) {
+ case IOMMU_DOMAIN_BLOCKED:
+ type = "blocked\n";
+ break;
+ case IOMMU_DOMAIN_IDENTITY:
+ type = "identity\n";
+ break;
+ case IOMMU_DOMAIN_UNMANAGED:
+ type = "unmanaged\n";
+ break;
+ case IOMMU_DOMAIN_DMA:
+ type = "DMA";
+ break;
+ }
+ }
+ strcpy(buf, type);
+
+ return strlen(type);
+}
+
+static IOMMU_GROUP_ATTR(name, S_IRUGO, iommu_group_show_name, NULL);
+
+static IOMMU_GROUP_ATTR(reserved_regions, 0444,
+ iommu_group_show_resv_regions, NULL);
+
+static IOMMU_GROUP_ATTR(type, 0444, iommu_group_show_type, NULL);
+
+static void iommu_group_release(struct kobject *kobj)
+{
+ struct iommu_group *group = to_iommu_group(kobj);
+
+ pr_debug("Releasing group %d\n", group->id);
+
+ if (group->iommu_data_release)
+ group->iommu_data_release(group->iommu_data);
+
+ ida_simple_remove(&iommu_group_ida, group->id);
+
+ if (group->default_domain)
+ iommu_domain_free(group->default_domain);
+
+ kfree(group->name);
+ kfree(group);
+}
+
+static struct kobj_type iommu_group_ktype = {
+ .sysfs_ops = &iommu_group_sysfs_ops,
+ .release = iommu_group_release,
+};
+
+/**
+ * iommu_group_alloc - Allocate a new group
+ *
+ * This function is called by an iommu driver to allocate a new iommu
+ * group. The iommu group represents the minimum granularity of the iommu.
+ * Upon successful return, the caller holds a reference to the supplied
+ * group in order to hold the group until devices are added. Use
+ * iommu_group_put() to release this extra reference count, allowing the
+ * group to be automatically reclaimed once it has no devices or external
+ * references.
+ */
+struct iommu_group *iommu_group_alloc(void)
+{
+ struct iommu_group *group;
+ int ret;
+
+ group = kzalloc(sizeof(*group), GFP_KERNEL);
+ if (!group)
+ return ERR_PTR(-ENOMEM);
+
+ group->kobj.kset = iommu_group_kset;
+ mutex_init(&group->mutex);
+ INIT_LIST_HEAD(&group->devices);
+ BLOCKING_INIT_NOTIFIER_HEAD(&group->notifier);
+
+ ret = ida_simple_get(&iommu_group_ida, 0, 0, GFP_KERNEL);
+ if (ret < 0) {
+ kfree(group);
+ return ERR_PTR(ret);
+ }
+ group->id = ret;
+
+ ret = kobject_init_and_add(&group->kobj, &iommu_group_ktype,
+ NULL, "%d", group->id);
+ if (ret) {
+ ida_simple_remove(&iommu_group_ida, group->id);
+ kfree(group);
+ return ERR_PTR(ret);
+ }
+
+ group->devices_kobj = kobject_create_and_add("devices", &group->kobj);
+ if (!group->devices_kobj) {
+ kobject_put(&group->kobj); /* triggers .release & free */
+ return ERR_PTR(-ENOMEM);
+ }
+
+ /*
+ * The devices_kobj holds a reference on the group kobject, so
+ * as long as that exists so will the group. We can therefore
+ * use the devices_kobj for reference counting.
+ */
+ kobject_put(&group->kobj);
+
+ ret = iommu_group_create_file(group,
+ &iommu_group_attr_reserved_regions);
+ if (ret)
+ return ERR_PTR(ret);
+
+ ret = iommu_group_create_file(group, &iommu_group_attr_type);
+ if (ret)
+ return ERR_PTR(ret);
+
+ pr_debug("Allocated group %d\n", group->id);
+
+ return group;
+}
+EXPORT_SYMBOL_GPL(iommu_group_alloc);
+
+struct iommu_group *iommu_group_get_by_id(int id)
+{
+ struct kobject *group_kobj;
+ struct iommu_group *group;
+ const char *name;
+
+ if (!iommu_group_kset)
+ return NULL;
+
+ name = kasprintf(GFP_KERNEL, "%d", id);
+ if (!name)
+ return NULL;
+
+ group_kobj = kset_find_obj(iommu_group_kset, name);
+ kfree(name);
+
+ if (!group_kobj)
+ return NULL;
+
+ group = container_of(group_kobj, struct iommu_group, kobj);
+ BUG_ON(group->id != id);
+
+ kobject_get(group->devices_kobj);
+ kobject_put(&group->kobj);
+
+ return group;
+}
+EXPORT_SYMBOL_GPL(iommu_group_get_by_id);
+
+/**
+ * iommu_group_get_iommudata - retrieve iommu_data registered for a group
+ * @group: the group
+ *
+ * iommu drivers can store data in the group for use when doing iommu
+ * operations. This function provides a way to retrieve it. Caller
+ * should hold a group reference.
+ */
+void *iommu_group_get_iommudata(struct iommu_group *group)
+{
+ return group->iommu_data;
+}
+EXPORT_SYMBOL_GPL(iommu_group_get_iommudata);
+
+/**
+ * iommu_group_set_iommudata - set iommu_data for a group
+ * @group: the group
+ * @iommu_data: new data
+ * @release: release function for iommu_data
+ *
+ * iommu drivers can store data in the group for use when doing iommu
+ * operations. This function provides a way to set the data after
+ * the group has been allocated. Caller should hold a group reference.
+ */
+void iommu_group_set_iommudata(struct iommu_group *group, void *iommu_data,
+ void (*release)(void *iommu_data))
+{
+ group->iommu_data = iommu_data;
+ group->iommu_data_release = release;
+}
+EXPORT_SYMBOL_GPL(iommu_group_set_iommudata);
+
+/**
+ * iommu_group_set_name - set name for a group
+ * @group: the group
+ * @name: name
+ *
+ * Allow iommu driver to set a name for a group. When set it will
+ * appear in a name attribute file under the group in sysfs.
+ */
+int iommu_group_set_name(struct iommu_group *group, const char *name)
+{
+ int ret;
+
+ if (group->name) {
+ iommu_group_remove_file(group, &iommu_group_attr_name);
+ kfree(group->name);
+ group->name = NULL;
+ if (!name)
+ return 0;
+ }
+
+ group->name = kstrdup(name, GFP_KERNEL);
+ if (!group->name)
+ return -ENOMEM;
+
+ ret = iommu_group_create_file(group, &iommu_group_attr_name);
+ if (ret) {
+ kfree(group->name);
+ group->name = NULL;
+ return ret;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(iommu_group_set_name);
+
+static int iommu_group_create_direct_mappings(struct iommu_group *group,
+ struct device *dev)
+{
+ struct iommu_domain *domain = group->default_domain;
+ struct iommu_resv_region *entry;
+ struct list_head mappings;
+ unsigned long pg_size;
+ int ret = 0;
+
+ if (!domain || domain->type != IOMMU_DOMAIN_DMA)
+ return 0;
+
+ BUG_ON(!domain->pgsize_bitmap);
+
+ pg_size = 1UL << __ffs(domain->pgsize_bitmap);
+ INIT_LIST_HEAD(&mappings);
+
+ iommu_get_resv_regions(dev, &mappings);
+
+ /* We need to consider overlapping regions for different devices */
+ list_for_each_entry(entry, &mappings, list) {
+ dma_addr_t start, end, addr;
+
+ if (domain->ops->apply_resv_region)
+ domain->ops->apply_resv_region(dev, domain, entry);
+
+ start = ALIGN(entry->start, pg_size);
+ end = ALIGN(entry->start + entry->length, pg_size);
+
+ if (entry->type != IOMMU_RESV_DIRECT)
+ continue;
+
+ for (addr = start; addr < end; addr += pg_size) {
+ phys_addr_t phys_addr;
+
+ phys_addr = iommu_iova_to_phys(domain, addr);
+ if (phys_addr)
+ continue;
+
+ ret = iommu_map(domain, addr, addr, pg_size, entry->prot);
+ if (ret)
+ goto out;
+ }
+
+ }
+
+ iommu_flush_tlb_all(domain);
+
+out:
+ iommu_put_resv_regions(dev, &mappings);
+
+ return ret;
+}
+
+/**
+ * iommu_group_add_device - add a device to an iommu group
+ * @group: the group into which to add the device (reference should be held)
+ * @dev: the device
+ *
+ * This function is called by an iommu driver to add a device into a
+ * group. Adding a device increments the group reference count.
+ */
+int iommu_group_add_device(struct iommu_group *group, struct device *dev)
+{
+ int ret, i = 0;
+ struct group_device *device;
+
+ device = kzalloc(sizeof(*device), GFP_KERNEL);
+ if (!device)
+ return -ENOMEM;
+
+ device->dev = dev;
+
+ ret = sysfs_create_link(&dev->kobj, &group->kobj, "iommu_group");
+ if (ret)
+ goto err_free_device;
+
+ device->name = kasprintf(GFP_KERNEL, "%s", kobject_name(&dev->kobj));
+rename:
+ if (!device->name) {
+ ret = -ENOMEM;
+ goto err_remove_link;
+ }
+
+ ret = sysfs_create_link_nowarn(group->devices_kobj,
+ &dev->kobj, device->name);
+ if (ret) {
+ if (ret == -EEXIST && i >= 0) {
+ /*
+ * Account for the slim chance of collision
+ * and append an instance to the name.
+ */
+ kfree(device->name);
+ device->name = kasprintf(GFP_KERNEL, "%s.%d",
+ kobject_name(&dev->kobj), i++);
+ goto rename;
+ }
+ goto err_free_name;
+ }
+
+ kobject_get(group->devices_kobj);
+
+ dev->iommu_group = group;
+
+ iommu_group_create_direct_mappings(group, dev);
+
+ mutex_lock(&group->mutex);
+ list_add_tail(&device->list, &group->devices);
+ if (group->domain)
+ ret = __iommu_attach_device(group->domain, dev);
+ mutex_unlock(&group->mutex);
+ if (ret)
+ goto err_put_group;
+
+ /* Notify any listeners about change to group. */
+ blocking_notifier_call_chain(&group->notifier,
+ IOMMU_GROUP_NOTIFY_ADD_DEVICE, dev);
+
+ trace_add_device_to_group(group->id, dev);
+
+ pr_info("Adding device %s to group %d\n", dev_name(dev), group->id);
+
+ return 0;
+
+err_put_group:
+ mutex_lock(&group->mutex);
+ list_del(&device->list);
+ mutex_unlock(&group->mutex);
+ dev->iommu_group = NULL;
+ kobject_put(group->devices_kobj);
+err_free_name:
+ kfree(device->name);
+err_remove_link:
+ sysfs_remove_link(&dev->kobj, "iommu_group");
+err_free_device:
+ kfree(device);
+ pr_err("Failed to add device %s to group %d: %d\n", dev_name(dev), group->id, ret);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iommu_group_add_device);
+
+/**
+ * iommu_group_remove_device - remove a device from it's current group
+ * @dev: device to be removed
+ *
+ * This function is called by an iommu driver to remove the device from
+ * it's current group. This decrements the iommu group reference count.
+ */
+void iommu_group_remove_device(struct device *dev)
+{
+ struct iommu_group *group = dev->iommu_group;
+ struct group_device *tmp_device, *device = NULL;
+
+ pr_info("Removing device %s from group %d\n", dev_name(dev), group->id);
+
+ /* Pre-notify listeners that a device is being removed. */
+ blocking_notifier_call_chain(&group->notifier,
+ IOMMU_GROUP_NOTIFY_DEL_DEVICE, dev);
+
+ mutex_lock(&group->mutex);
+ list_for_each_entry(tmp_device, &group->devices, list) {
+ if (tmp_device->dev == dev) {
+ device = tmp_device;
+ list_del(&device->list);
+ break;
+ }
+ }
+ mutex_unlock(&group->mutex);
+
+ if (!device)
+ return;
+
+ sysfs_remove_link(group->devices_kobj, device->name);
+ sysfs_remove_link(&dev->kobj, "iommu_group");
+
+ trace_remove_device_from_group(group->id, dev);
+
+ kfree(device->name);
+ kfree(device);
+ dev->iommu_group = NULL;
+ kobject_put(group->devices_kobj);
+}
+EXPORT_SYMBOL_GPL(iommu_group_remove_device);
+
+static int iommu_group_device_count(struct iommu_group *group)
+{
+ struct group_device *entry;
+ int ret = 0;
+
+ list_for_each_entry(entry, &group->devices, list)
+ ret++;
+
+ return ret;
+}
+
+/**
+ * iommu_group_for_each_dev - iterate over each device in the group
+ * @group: the group
+ * @data: caller opaque data to be passed to callback function
+ * @fn: caller supplied callback function
+ *
+ * This function is called by group users to iterate over group devices.
+ * Callers should hold a reference count to the group during callback.
+ * The group->mutex is held across callbacks, which will block calls to
+ * iommu_group_add/remove_device.
+ */
+static int __iommu_group_for_each_dev(struct iommu_group *group, void *data,
+ int (*fn)(struct device *, void *))
+{
+ struct group_device *device;
+ int ret = 0;
+
+ list_for_each_entry(device, &group->devices, list) {
+ ret = fn(device->dev, data);
+ if (ret)
+ break;
+ }
+ return ret;
+}
+
+
+int iommu_group_for_each_dev(struct iommu_group *group, void *data,
+ int (*fn)(struct device *, void *))
+{
+ int ret;
+
+ mutex_lock(&group->mutex);
+ ret = __iommu_group_for_each_dev(group, data, fn);
+ mutex_unlock(&group->mutex);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iommu_group_for_each_dev);
+
+/**
+ * iommu_group_get - Return the group for a device and increment reference
+ * @dev: get the group that this device belongs to
+ *
+ * This function is called by iommu drivers and users to get the group
+ * for the specified device. If found, the group is returned and the group
+ * reference in incremented, else NULL.
+ */
+struct iommu_group *iommu_group_get(struct device *dev)
+{
+ struct iommu_group *group = dev->iommu_group;
+
+ if (group)
+ kobject_get(group->devices_kobj);
+
+ return group;
+}
+EXPORT_SYMBOL_GPL(iommu_group_get);
+
+/**
+ * iommu_group_ref_get - Increment reference on a group
+ * @group: the group to use, must not be NULL
+ *
+ * This function is called by iommu drivers to take additional references on an
+ * existing group. Returns the given group for convenience.
+ */
+struct iommu_group *iommu_group_ref_get(struct iommu_group *group)
+{
+ kobject_get(group->devices_kobj);
+ return group;
+}
+
+/**
+ * iommu_group_put - Decrement group reference
+ * @group: the group to use
+ *
+ * This function is called by iommu drivers and users to release the
+ * iommu group. Once the reference count is zero, the group is released.
+ */
+void iommu_group_put(struct iommu_group *group)
+{
+ if (group)
+ kobject_put(group->devices_kobj);
+}
+EXPORT_SYMBOL_GPL(iommu_group_put);
+
+/**
+ * iommu_group_register_notifier - Register a notifier for group changes
+ * @group: the group to watch
+ * @nb: notifier block to signal
+ *
+ * This function allows iommu group users to track changes in a group.
+ * See include/linux/iommu.h for actions sent via this notifier. Caller
+ * should hold a reference to the group throughout notifier registration.
+ */
+int iommu_group_register_notifier(struct iommu_group *group,
+ struct notifier_block *nb)
+{
+ return blocking_notifier_chain_register(&group->notifier, nb);
+}
+EXPORT_SYMBOL_GPL(iommu_group_register_notifier);
+
+/**
+ * iommu_group_unregister_notifier - Unregister a notifier
+ * @group: the group to watch
+ * @nb: notifier block to signal
+ *
+ * Unregister a previously registered group notifier block.
+ */
+int iommu_group_unregister_notifier(struct iommu_group *group,
+ struct notifier_block *nb)
+{
+ return blocking_notifier_chain_unregister(&group->notifier, nb);
+}
+EXPORT_SYMBOL_GPL(iommu_group_unregister_notifier);
+
+/**
+ * iommu_group_id - Return ID for a group
+ * @group: the group to ID
+ *
+ * Return the unique ID for the group matching the sysfs group number.
+ */
+int iommu_group_id(struct iommu_group *group)
+{
+ return group->id;
+}
+EXPORT_SYMBOL_GPL(iommu_group_id);
+
+static struct iommu_group *get_pci_alias_group(struct pci_dev *pdev,
+ unsigned long *devfns);
+
+/*
+ * To consider a PCI device isolated, we require ACS to support Source
+ * Validation, Request Redirection, Completer Redirection, and Upstream
+ * Forwarding. This effectively means that devices cannot spoof their
+ * requester ID, requests and completions cannot be redirected, and all
+ * transactions are forwarded upstream, even as it passes through a
+ * bridge where the target device is downstream.
+ */
+#define REQ_ACS_FLAGS (PCI_ACS_SV | PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF)
+
+/*
+ * For multifunction devices which are not isolated from each other, find
+ * all the other non-isolated functions and look for existing groups. For
+ * each function, we also need to look for aliases to or from other devices
+ * that may already have a group.
+ */
+static struct iommu_group *get_pci_function_alias_group(struct pci_dev *pdev,
+ unsigned long *devfns)
+{
+ struct pci_dev *tmp = NULL;
+ struct iommu_group *group;
+
+ if (!pdev->multifunction || pci_acs_enabled(pdev, REQ_ACS_FLAGS))
+ return NULL;
+
+ for_each_pci_dev(tmp) {
+ if (tmp == pdev || tmp->bus != pdev->bus ||
+ PCI_SLOT(tmp->devfn) != PCI_SLOT(pdev->devfn) ||
+ pci_acs_enabled(tmp, REQ_ACS_FLAGS))
+ continue;
+
+ group = get_pci_alias_group(tmp, devfns);
+ if (group) {
+ pci_dev_put(tmp);
+ return group;
+ }
+ }
+
+ return NULL;
+}
+
+/*
+ * Look for aliases to or from the given device for existing groups. DMA
+ * aliases are only supported on the same bus, therefore the search
+ * space is quite small (especially since we're really only looking at pcie
+ * device, and therefore only expect multiple slots on the root complex or
+ * downstream switch ports). It's conceivable though that a pair of
+ * multifunction devices could have aliases between them that would cause a
+ * loop. To prevent this, we use a bitmap to track where we've been.
+ */
+static struct iommu_group *get_pci_alias_group(struct pci_dev *pdev,
+ unsigned long *devfns)
+{
+ struct pci_dev *tmp = NULL;
+ struct iommu_group *group;
+
+ if (test_and_set_bit(pdev->devfn & 0xff, devfns))
+ return NULL;
+
+ group = iommu_group_get(&pdev->dev);
+ if (group)
+ return group;
+
+ for_each_pci_dev(tmp) {
+ if (tmp == pdev || tmp->bus != pdev->bus)
+ continue;
+
+ /* We alias them or they alias us */
+ if (pci_devs_are_dma_aliases(pdev, tmp)) {
+ group = get_pci_alias_group(tmp, devfns);
+ if (group) {
+ pci_dev_put(tmp);
+ return group;
+ }
+
+ group = get_pci_function_alias_group(tmp, devfns);
+ if (group) {
+ pci_dev_put(tmp);
+ return group;
+ }
+ }
+ }
+
+ return NULL;
+}
+
+struct group_for_pci_data {
+ struct pci_dev *pdev;
+ struct iommu_group *group;
+};
+
+/*
+ * DMA alias iterator callback, return the last seen device. Stop and return
+ * the IOMMU group if we find one along the way.
+ */
+static int get_pci_alias_or_group(struct pci_dev *pdev, u16 alias, void *opaque)
+{
+ struct group_for_pci_data *data = opaque;
+
+ data->pdev = pdev;
+ data->group = iommu_group_get(&pdev->dev);
+
+ return data->group != NULL;
+}
+
+/*
+ * Generic device_group call-back function. It just allocates one
+ * iommu-group per device.
+ */
+struct iommu_group *generic_device_group(struct device *dev)
+{
+ return iommu_group_alloc();
+}
+
+/*
+ * Use standard PCI bus topology, isolation features, and DMA alias quirks
+ * to find or create an IOMMU group for a device.
+ */
+struct iommu_group *pci_device_group(struct device *dev)
+{
+ struct pci_dev *pdev = to_pci_dev(dev);
+ struct group_for_pci_data data;
+ struct pci_bus *bus;
+ struct iommu_group *group = NULL;
+ u64 devfns[4] = { 0 };
+
+ if (WARN_ON(!dev_is_pci(dev)))
+ return ERR_PTR(-EINVAL);
+
+ /*
+ * Find the upstream DMA alias for the device. A device must not
+ * be aliased due to topology in order to have its own IOMMU group.
+ * If we find an alias along the way that already belongs to a
+ * group, use it.
+ */
+ if (pci_for_each_dma_alias(pdev, get_pci_alias_or_group, &data))
+ return data.group;
+
+ pdev = data.pdev;
+
+ /*
+ * Continue upstream from the point of minimum IOMMU granularity
+ * due to aliases to the point where devices are protected from
+ * peer-to-peer DMA by PCI ACS. Again, if we find an existing
+ * group, use it.
+ */
+ for (bus = pdev->bus; !pci_is_root_bus(bus); bus = bus->parent) {
+ if (!bus->self)
+ continue;
+
+ if (pci_acs_path_enabled(bus->self, NULL, REQ_ACS_FLAGS))
+ break;
+
+ pdev = bus->self;
+
+ group = iommu_group_get(&pdev->dev);
+ if (group)
+ return group;
+ }
+
+ /*
+ * Look for existing groups on device aliases. If we alias another
+ * device or another device aliases us, use the same group.
+ */
+ group = get_pci_alias_group(pdev, (unsigned long *)devfns);
+ if (group)
+ return group;
+
+ /*
+ * Look for existing groups on non-isolated functions on the same
+ * slot and aliases of those funcions, if any. No need to clear
+ * the search bitmap, the tested devfns are still valid.
+ */
+ group = get_pci_function_alias_group(pdev, (unsigned long *)devfns);
+ if (group)
+ return group;
+
+ /* No shared group found, allocate new */
+ return iommu_group_alloc();
+}
+
+/**
+ * iommu_group_get_for_dev - Find or create the IOMMU group for a device
+ * @dev: target device
+ *
+ * This function is intended to be called by IOMMU drivers and extended to
+ * support common, bus-defined algorithms when determining or creating the
+ * IOMMU group for a device. On success, the caller will hold a reference
+ * to the returned IOMMU group, which will already include the provided
+ * device. The reference should be released with iommu_group_put().
+ */
+struct iommu_group *iommu_group_get_for_dev(struct device *dev)
+{
+ const struct iommu_ops *ops = dev->bus->iommu_ops;
+ struct iommu_group *group;
+ int ret;
+
+ group = iommu_group_get(dev);
+ if (group)
+ return group;
+
+ if (!ops)
+ return ERR_PTR(-EINVAL);
+
+ group = ops->device_group(dev);
+ if (WARN_ON_ONCE(group == NULL))
+ return ERR_PTR(-EINVAL);
+
+ if (IS_ERR(group))
+ return group;
+
+ /*
+ * Try to allocate a default domain - needs support from the
+ * IOMMU driver.
+ */
+ if (!group->default_domain) {
+ struct iommu_domain *dom;
+
+ dom = __iommu_domain_alloc(dev->bus, iommu_def_domain_type);
+ if (!dom && iommu_def_domain_type != IOMMU_DOMAIN_DMA) {
+ dev_warn(dev,
+ "failed to allocate default IOMMU domain of type %u; falling back to IOMMU_DOMAIN_DMA",
+ iommu_def_domain_type);
+ dom = __iommu_domain_alloc(dev->bus, IOMMU_DOMAIN_DMA);
+ }
+
+ group->default_domain = dom;
+ if (!group->domain)
+ group->domain = dom;
+ }
+
+ ret = iommu_group_add_device(group, dev);
+ if (ret) {
+ iommu_group_put(group);
+ return ERR_PTR(ret);
+ }
+
+ return group;
+}
+
+struct iommu_domain *iommu_group_default_domain(struct iommu_group *group)
+{
+ return group->default_domain;
+}
+
+static int add_iommu_group(struct device *dev, void *data)
+{
+ struct iommu_callback_data *cb = data;
+ const struct iommu_ops *ops = cb->ops;
+ int ret;
+
+ if (!ops->add_device)
+ return 0;
+
+ WARN_ON(dev->iommu_group);
+
+ ret = ops->add_device(dev);
+
+ /*
+ * We ignore -ENODEV errors for now, as they just mean that the
+ * device is not translated by an IOMMU. We still care about
+ * other errors and fail to initialize when they happen.
+ */
+ if (ret == -ENODEV)
+ ret = 0;
+
+ return ret;
+}
+
+static int remove_iommu_group(struct device *dev, void *data)
+{
+ struct iommu_callback_data *cb = data;
+ const struct iommu_ops *ops = cb->ops;
+
+ if (ops->remove_device && dev->iommu_group)
+ ops->remove_device(dev);
+
+ return 0;
+}
+
+static int iommu_bus_notifier(struct notifier_block *nb,
+ unsigned long action, void *data)
+{
+ struct device *dev = data;
+ const struct iommu_ops *ops = dev->bus->iommu_ops;
+ struct iommu_group *group;
+ unsigned long group_action = 0;
+
+ /*
+ * ADD/DEL call into iommu driver ops if provided, which may
+ * result in ADD/DEL notifiers to group->notifier
+ */
+ if (action == BUS_NOTIFY_ADD_DEVICE) {
+ if (ops->add_device) {
+ int ret;
+
+ ret = ops->add_device(dev);
+ return (ret) ? NOTIFY_DONE : NOTIFY_OK;
+ }
+ } else if (action == BUS_NOTIFY_REMOVED_DEVICE) {
+ if (ops->remove_device && dev->iommu_group) {
+ ops->remove_device(dev);
+ return 0;
+ }
+ }
+
+ /*
+ * Remaining BUS_NOTIFYs get filtered and republished to the
+ * group, if anyone is listening
+ */
+ group = iommu_group_get(dev);
+ if (!group)
+ return 0;
+
+ switch (action) {
+ case BUS_NOTIFY_BIND_DRIVER:
+ group_action = IOMMU_GROUP_NOTIFY_BIND_DRIVER;
+ break;
+ case BUS_NOTIFY_BOUND_DRIVER:
+ group_action = IOMMU_GROUP_NOTIFY_BOUND_DRIVER;
+ break;
+ case BUS_NOTIFY_UNBIND_DRIVER:
+ group_action = IOMMU_GROUP_NOTIFY_UNBIND_DRIVER;
+ break;
+ case BUS_NOTIFY_UNBOUND_DRIVER:
+ group_action = IOMMU_GROUP_NOTIFY_UNBOUND_DRIVER;
+ break;
+ }
+
+ if (group_action)
+ blocking_notifier_call_chain(&group->notifier,
+ group_action, dev);
+
+ iommu_group_put(group);
+ return 0;
+}
+
+static int iommu_bus_init(struct bus_type *bus, const struct iommu_ops *ops)
+{
+ int err;
+ struct notifier_block *nb;
+ struct iommu_callback_data cb = {
+ .ops = ops,
+ };
+
+ nb = kzalloc(sizeof(struct notifier_block), GFP_KERNEL);
+ if (!nb)
+ return -ENOMEM;
+
+ nb->notifier_call = iommu_bus_notifier;
+
+ err = bus_register_notifier(bus, nb);
+ if (err)
+ goto out_free;
+
+ err = bus_for_each_dev(bus, NULL, &cb, add_iommu_group);
+ if (err)
+ goto out_err;
+
+
+ return 0;
+
+out_err:
+ /* Clean up */
+ bus_for_each_dev(bus, NULL, &cb, remove_iommu_group);
+ bus_unregister_notifier(bus, nb);
+
+out_free:
+ kfree(nb);
+
+ return err;
+}
+
+/**
+ * bus_set_iommu - set iommu-callbacks for the bus
+ * @bus: bus.
+ * @ops: the callbacks provided by the iommu-driver
+ *
+ * This function is called by an iommu driver to set the iommu methods
+ * used for a particular bus. Drivers for devices on that bus can use
+ * the iommu-api after these ops are registered.
+ * This special function is needed because IOMMUs are usually devices on
+ * the bus itself, so the iommu drivers are not initialized when the bus
+ * is set up. With this function the iommu-driver can set the iommu-ops
+ * afterwards.
+ */
+int bus_set_iommu(struct bus_type *bus, const struct iommu_ops *ops)
+{
+ int err;
+
+ if (bus->iommu_ops != NULL)
+ return -EBUSY;
+
+ bus->iommu_ops = ops;
+
+ /* Do IOMMU specific setup for this bus-type */
+ err = iommu_bus_init(bus, ops);
+ if (err)
+ bus->iommu_ops = NULL;
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(bus_set_iommu);
+
+bool iommu_present(struct bus_type *bus)
+{
+ return bus->iommu_ops != NULL;
+}
+EXPORT_SYMBOL_GPL(iommu_present);
+
+bool iommu_capable(struct bus_type *bus, enum iommu_cap cap)
+{
+ if (!bus->iommu_ops || !bus->iommu_ops->capable)
+ return false;
+
+ return bus->iommu_ops->capable(cap);
+}
+EXPORT_SYMBOL_GPL(iommu_capable);
+
+/**
+ * iommu_set_fault_handler() - set a fault handler for an iommu domain
+ * @domain: iommu domain
+ * @handler: fault handler
+ * @token: user data, will be passed back to the fault handler
+ *
+ * This function should be used by IOMMU users which want to be notified
+ * whenever an IOMMU fault happens.
+ *
+ * The fault handler itself should return 0 on success, and an appropriate
+ * error code otherwise.
+ */
+void iommu_set_fault_handler(struct iommu_domain *domain,
+ iommu_fault_handler_t handler,
+ void *token)
+{
+ BUG_ON(!domain);
+
+ domain->handler = handler;
+ domain->handler_token = token;
+}
+EXPORT_SYMBOL_GPL(iommu_set_fault_handler);
+
+static struct iommu_domain *__iommu_domain_alloc(struct bus_type *bus,
+ unsigned type)
+{
+ struct iommu_domain *domain;
+
+ if (bus == NULL || bus->iommu_ops == NULL)
+ return NULL;
+
+ domain = bus->iommu_ops->domain_alloc(type);
+ if (!domain)
+ return NULL;
+
+ domain->ops = bus->iommu_ops;
+ domain->type = type;
+ /* Assume all sizes by default; the driver may override this later */
+ domain->pgsize_bitmap = bus->iommu_ops->pgsize_bitmap;
+
+ return domain;
+}
+
+struct iommu_domain *iommu_domain_alloc(struct bus_type *bus)
+{
+ return __iommu_domain_alloc(bus, IOMMU_DOMAIN_UNMANAGED);
+}
+EXPORT_SYMBOL_GPL(iommu_domain_alloc);
+
+void iommu_domain_free(struct iommu_domain *domain)
+{
+ domain->ops->domain_free(domain);
+}
+EXPORT_SYMBOL_GPL(iommu_domain_free);
+
+static int __iommu_attach_device(struct iommu_domain *domain,
+ struct device *dev)
+{
+ int ret;
+ if ((domain->ops->is_attach_deferred != NULL) &&
+ domain->ops->is_attach_deferred(domain, dev))
+ return 0;
+
+ if (unlikely(domain->ops->attach_dev == NULL))
+ return -ENODEV;
+
+ ret = domain->ops->attach_dev(domain, dev);
+ if (!ret)
+ trace_attach_device_to_domain(dev);
+ return ret;
+}
+
+int iommu_attach_device(struct iommu_domain *domain, struct device *dev)
+{
+ struct iommu_group *group;
+ int ret;
+
+ group = iommu_group_get(dev);
+ if (!group)
+ return -ENODEV;
+
+ /*
+ * Lock the group to make sure the device-count doesn't
+ * change while we are attaching
+ */
+ mutex_lock(&group->mutex);
+ ret = -EINVAL;
+ if (iommu_group_device_count(group) != 1)
+ goto out_unlock;
+
+ ret = __iommu_attach_group(domain, group);
+
+out_unlock:
+ mutex_unlock(&group->mutex);
+ iommu_group_put(group);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iommu_attach_device);
+
+static void __iommu_detach_device(struct iommu_domain *domain,
+ struct device *dev)
+{
+ if ((domain->ops->is_attach_deferred != NULL) &&
+ domain->ops->is_attach_deferred(domain, dev))
+ return;
+
+ if (unlikely(domain->ops->detach_dev == NULL))
+ return;
+
+ domain->ops->detach_dev(domain, dev);
+ trace_detach_device_from_domain(dev);
+}
+
+void iommu_detach_device(struct iommu_domain *domain, struct device *dev)
+{
+ struct iommu_group *group;
+
+ group = iommu_group_get(dev);
+ if (!group)
+ return;
+
+ mutex_lock(&group->mutex);
+ if (iommu_group_device_count(group) != 1) {
+ WARN_ON(1);
+ goto out_unlock;
+ }
+
+ __iommu_detach_group(domain, group);
+
+out_unlock:
+ mutex_unlock(&group->mutex);
+ iommu_group_put(group);
+}
+EXPORT_SYMBOL_GPL(iommu_detach_device);
+
+struct iommu_domain *iommu_get_domain_for_dev(struct device *dev)
+{
+ struct iommu_domain *domain;
+ struct iommu_group *group;
+
+ group = iommu_group_get(dev);
+ if (!group)
+ return NULL;
+
+ domain = group->domain;
+
+ iommu_group_put(group);
+
+ return domain;
+}
+EXPORT_SYMBOL_GPL(iommu_get_domain_for_dev);
+
+/*
+ * IOMMU groups are really the natrual working unit of the IOMMU, but
+ * the IOMMU API works on domains and devices. Bridge that gap by
+ * iterating over the devices in a group. Ideally we'd have a single
+ * device which represents the requestor ID of the group, but we also
+ * allow IOMMU drivers to create policy defined minimum sets, where
+ * the physical hardware may be able to distiguish members, but we
+ * wish to group them at a higher level (ex. untrusted multi-function
+ * PCI devices). Thus we attach each device.
+ */
+static int iommu_group_do_attach_device(struct device *dev, void *data)
+{
+ struct iommu_domain *domain = data;
+
+ return __iommu_attach_device(domain, dev);
+}
+
+static int __iommu_attach_group(struct iommu_domain *domain,
+ struct iommu_group *group)
+{
+ int ret;
+
+ if (group->default_domain && group->domain != group->default_domain)
+ return -EBUSY;
+
+ ret = __iommu_group_for_each_dev(group, domain,
+ iommu_group_do_attach_device);
+ if (ret == 0)
+ group->domain = domain;
+
+ return ret;
+}
+
+int iommu_attach_group(struct iommu_domain *domain, struct iommu_group *group)
+{
+ int ret;
+
+ mutex_lock(&group->mutex);
+ ret = __iommu_attach_group(domain, group);
+ mutex_unlock(&group->mutex);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iommu_attach_group);
+
+static int iommu_group_do_detach_device(struct device *dev, void *data)
+{
+ struct iommu_domain *domain = data;
+
+ __iommu_detach_device(domain, dev);
+
+ return 0;
+}
+
+static void __iommu_detach_group(struct iommu_domain *domain,
+ struct iommu_group *group)
+{
+ int ret;
+
+ if (!group->default_domain) {
+ __iommu_group_for_each_dev(group, domain,
+ iommu_group_do_detach_device);
+ group->domain = NULL;
+ return;
+ }
+
+ if (group->domain == group->default_domain)
+ return;
+
+ /* Detach by re-attaching to the default domain */
+ ret = __iommu_group_for_each_dev(group, group->default_domain,
+ iommu_group_do_attach_device);
+ if (ret != 0)
+ WARN_ON(1);
+ else
+ group->domain = group->default_domain;
+}
+
+void iommu_detach_group(struct iommu_domain *domain, struct iommu_group *group)
+{
+ mutex_lock(&group->mutex);
+ __iommu_detach_group(domain, group);
+ mutex_unlock(&group->mutex);
+}
+EXPORT_SYMBOL_GPL(iommu_detach_group);
+
+phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain, dma_addr_t iova)
+{
+ if (unlikely(domain->ops->iova_to_phys == NULL))
+ return 0;
+
+ return domain->ops->iova_to_phys(domain, iova);
+}
+EXPORT_SYMBOL_GPL(iommu_iova_to_phys);
+
+static size_t iommu_pgsize(struct iommu_domain *domain,
+ unsigned long addr_merge, size_t size)
+{
+ unsigned int pgsize_idx;
+ size_t pgsize;
+
+ /* Max page size that still fits into 'size' */
+ pgsize_idx = __fls(size);
+
+ /* need to consider alignment requirements ? */
+ if (likely(addr_merge)) {
+ /* Max page size allowed by address */
+ unsigned int align_pgsize_idx = __ffs(addr_merge);
+ pgsize_idx = min(pgsize_idx, align_pgsize_idx);
+ }
+
+ /* build a mask of acceptable page sizes */
+ pgsize = (1UL << (pgsize_idx + 1)) - 1;
+
+ /* throw away page sizes not supported by the hardware */
+ pgsize &= domain->pgsize_bitmap;
+
+ /* make sure we're still sane */
+ BUG_ON(!pgsize);
+
+ /* pick the biggest page */
+ pgsize_idx = __fls(pgsize);
+ pgsize = 1UL << pgsize_idx;
+
+ return pgsize;
+}
+
+int iommu_map(struct iommu_domain *domain, unsigned long iova,
+ phys_addr_t paddr, size_t size, int prot)
+{
+ unsigned long orig_iova = iova;
+ unsigned int min_pagesz;
+ size_t orig_size = size;
+ phys_addr_t orig_paddr = paddr;
+ int ret = 0;
+
+ if (unlikely(domain->ops->map == NULL ||
+ domain->pgsize_bitmap == 0UL))
+ return -ENODEV;
+
+ if (unlikely(!(domain->type & __IOMMU_DOMAIN_PAGING)))
+ return -EINVAL;
+
+ /* find out the minimum page size supported */
+ min_pagesz = 1 << __ffs(domain->pgsize_bitmap);
+
+ /*
+ * both the virtual address and the physical one, as well as
+ * the size of the mapping, must be aligned (at least) to the
+ * size of the smallest page supported by the hardware
+ */
+ if (!IS_ALIGNED(iova | paddr | size, min_pagesz)) {
+ pr_err("unaligned: iova 0x%lx pa %pa size 0x%zx min_pagesz 0x%x\n",
+ iova, &paddr, size, min_pagesz);
+ return -EINVAL;
+ }
+
+ pr_debug("map: iova 0x%lx pa %pa size 0x%zx\n", iova, &paddr, size);
+
+ while (size) {
+ size_t pgsize = iommu_pgsize(domain, iova | paddr, size);
+
+ pr_debug("mapping: iova 0x%lx pa %pa pgsize 0x%zx\n",
+ iova, &paddr, pgsize);
+
+ ret = domain->ops->map(domain, iova, paddr, pgsize, prot);
+ if (ret)
+ break;
+
+ iova += pgsize;
+ paddr += pgsize;
+ size -= pgsize;
+ }
+
+ /* unroll mapping in case something went wrong */
+ if (ret)
+ iommu_unmap(domain, orig_iova, orig_size - size);
+ else
+ trace_map(orig_iova, orig_paddr, orig_size);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iommu_map);
+
+static size_t __iommu_unmap(struct iommu_domain *domain,
+ unsigned long iova, size_t size,
+ bool sync)
+{
+ const struct iommu_ops *ops = domain->ops;
+ size_t unmapped_page, unmapped = 0;
+ unsigned long orig_iova = iova;
+ unsigned int min_pagesz;
+
+ if (unlikely(ops->unmap == NULL ||
+ domain->pgsize_bitmap == 0UL))
+ return 0;
+
+ if (unlikely(!(domain->type & __IOMMU_DOMAIN_PAGING)))
+ return 0;
+
+ /* find out the minimum page size supported */
+ min_pagesz = 1 << __ffs(domain->pgsize_bitmap);
+
+ /*
+ * The virtual address, as well as the size of the mapping, must be
+ * aligned (at least) to the size of the smallest page supported
+ * by the hardware
+ */
+ if (!IS_ALIGNED(iova | size, min_pagesz)) {
+ pr_err("unaligned: iova 0x%lx size 0x%zx min_pagesz 0x%x\n",
+ iova, size, min_pagesz);
+ return 0;
+ }
+
+ pr_debug("unmap this: iova 0x%lx size 0x%zx\n", iova, size);
+
+ /*
+ * Keep iterating until we either unmap 'size' bytes (or more)
+ * or we hit an area that isn't mapped.
+ */
+ while (unmapped < size) {
+ size_t pgsize = iommu_pgsize(domain, iova, size - unmapped);
+
+ unmapped_page = ops->unmap(domain, iova, pgsize);
+ if (!unmapped_page)
+ break;
+
+ if (sync && ops->iotlb_range_add)
+ ops->iotlb_range_add(domain, iova, pgsize);
+
+ pr_debug("unmapped: iova 0x%lx size 0x%zx\n",
+ iova, unmapped_page);
+
+ iova += unmapped_page;
+ unmapped += unmapped_page;
+ }
+
+ if (sync && ops->iotlb_sync)
+ ops->iotlb_sync(domain);
+
+ trace_unmap(orig_iova, size, unmapped);
+ return unmapped;
+}
+
+size_t iommu_unmap(struct iommu_domain *domain,
+ unsigned long iova, size_t size)
+{
+ return __iommu_unmap(domain, iova, size, true);
+}
+EXPORT_SYMBOL_GPL(iommu_unmap);
+
+size_t iommu_unmap_fast(struct iommu_domain *domain,
+ unsigned long iova, size_t size)
+{
+ return __iommu_unmap(domain, iova, size, false);
+}
+EXPORT_SYMBOL_GPL(iommu_unmap_fast);
+
+size_t iommu_map_sg(struct iommu_domain *domain, unsigned long iova,
+ struct scatterlist *sg, unsigned int nents, int prot)
+{
+ struct scatterlist *s;
+ size_t mapped = 0;
+ unsigned int i, min_pagesz;
+ int ret;
+
+ if (unlikely(domain->pgsize_bitmap == 0UL))
+ return 0;
+
+ min_pagesz = 1 << __ffs(domain->pgsize_bitmap);
+
+ for_each_sg(sg, s, nents, i) {
+ phys_addr_t phys = page_to_phys(sg_page(s)) + s->offset;
+
+ /*
+ * We are mapping on IOMMU page boundaries, so offset within
+ * the page must be 0. However, the IOMMU may support pages
+ * smaller than PAGE_SIZE, so s->offset may still represent
+ * an offset of that boundary within the CPU page.
+ */
+ if (!IS_ALIGNED(s->offset, min_pagesz))
+ goto out_err;
+
+ ret = iommu_map(domain, iova + mapped, phys, s->length, prot);
+ if (ret)
+ goto out_err;
+
+ mapped += s->length;
+ }
+
+ return mapped;
+
+out_err:
+ /* undo mappings already done */
+ iommu_unmap(domain, iova, mapped);
+
+ return 0;
+
+}
+EXPORT_SYMBOL_GPL(iommu_map_sg);
+
+int iommu_domain_window_enable(struct iommu_domain *domain, u32 wnd_nr,
+ phys_addr_t paddr, u64 size, int prot)
+{
+ if (unlikely(domain->ops->domain_window_enable == NULL))
+ return -ENODEV;
+
+ return domain->ops->domain_window_enable(domain, wnd_nr, paddr, size,
+ prot);
+}
+EXPORT_SYMBOL_GPL(iommu_domain_window_enable);
+
+void iommu_domain_window_disable(struct iommu_domain *domain, u32 wnd_nr)
+{
+ if (unlikely(domain->ops->domain_window_disable == NULL))
+ return;
+
+ return domain->ops->domain_window_disable(domain, wnd_nr);
+}
+EXPORT_SYMBOL_GPL(iommu_domain_window_disable);
+
+/**
+ * report_iommu_fault() - report about an IOMMU fault to the IOMMU framework
+ * @domain: the iommu domain where the fault has happened
+ * @dev: the device where the fault has happened
+ * @iova: the faulting address
+ * @flags: mmu fault flags (e.g. IOMMU_FAULT_READ/IOMMU_FAULT_WRITE/...)
+ *
+ * This function should be called by the low-level IOMMU implementations
+ * whenever IOMMU faults happen, to allow high-level users, that are
+ * interested in such events, to know about them.
+ *
+ * This event may be useful for several possible use cases:
+ * - mere logging of the event
+ * - dynamic TLB/PTE loading
+ * - if restarting of the faulting device is required
+ *
+ * Returns 0 on success and an appropriate error code otherwise (if dynamic
+ * PTE/TLB loading will one day be supported, implementations will be able
+ * to tell whether it succeeded or not according to this return value).
+ *
+ * Specifically, -ENOSYS is returned if a fault handler isn't installed
+ * (though fault handlers can also return -ENOSYS, in case they want to
+ * elicit the default behavior of the IOMMU drivers).
+ */
+int report_iommu_fault(struct iommu_domain *domain, struct device *dev,
+ unsigned long iova, int flags)
+{
+ int ret = -ENOSYS;
+
+ /*
+ * if upper layers showed interest and installed a fault handler,
+ * invoke it.
+ */
+ if (domain->handler)
+ ret = domain->handler(domain, dev, iova, flags,
+ domain->handler_token);
+
+ trace_io_page_fault(dev, iova, flags);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(report_iommu_fault);
+
+static int __init iommu_init(void)
+{
+ iommu_group_kset = kset_create_and_add("iommu_groups",
+ NULL, kernel_kobj);
+ BUG_ON(!iommu_group_kset);
+
+ iommu_debugfs_setup();
+
+ return 0;
+}
+core_initcall(iommu_init);
+
+int iommu_domain_get_attr(struct iommu_domain *domain,
+ enum iommu_attr attr, void *data)
+{
+ struct iommu_domain_geometry *geometry;
+ bool *paging;
+ int ret = 0;
+ u32 *count;
+
+ switch (attr) {
+ case DOMAIN_ATTR_GEOMETRY:
+ geometry = data;
+ *geometry = domain->geometry;
+
+ break;
+ case DOMAIN_ATTR_PAGING:
+ paging = data;
+ *paging = (domain->pgsize_bitmap != 0UL);
+ break;
+ case DOMAIN_ATTR_WINDOWS:
+ count = data;
+
+ if (domain->ops->domain_get_windows != NULL)
+ *count = domain->ops->domain_get_windows(domain);
+ else
+ ret = -ENODEV;
+
+ break;
+ default:
+ if (!domain->ops->domain_get_attr)
+ return -EINVAL;
+
+ ret = domain->ops->domain_get_attr(domain, attr, data);
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iommu_domain_get_attr);
+
+int iommu_domain_set_attr(struct iommu_domain *domain,
+ enum iommu_attr attr, void *data)
+{
+ int ret = 0;
+ u32 *count;
+
+ switch (attr) {
+ case DOMAIN_ATTR_WINDOWS:
+ count = data;
+
+ if (domain->ops->domain_set_windows != NULL)
+ ret = domain->ops->domain_set_windows(domain, *count);
+ else
+ ret = -ENODEV;
+
+ break;
+ default:
+ if (domain->ops->domain_set_attr == NULL)
+ return -EINVAL;
+
+ ret = domain->ops->domain_set_attr(domain, attr, data);
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iommu_domain_set_attr);
+
+void iommu_get_resv_regions(struct device *dev, struct list_head *list)
+{
+ const struct iommu_ops *ops = dev->bus->iommu_ops;
+
+ if (ops && ops->get_resv_regions)
+ ops->get_resv_regions(dev, list);
+}
+
+void iommu_put_resv_regions(struct device *dev, struct list_head *list)
+{
+ const struct iommu_ops *ops = dev->bus->iommu_ops;
+
+ if (ops && ops->put_resv_regions)
+ ops->put_resv_regions(dev, list);
+}
+
+struct iommu_resv_region *iommu_alloc_resv_region(phys_addr_t start,
+ size_t length, int prot,
+ enum iommu_resv_type type)
+{
+ struct iommu_resv_region *region;
+
+ region = kzalloc(sizeof(*region), GFP_KERNEL);
+ if (!region)
+ return NULL;
+
+ INIT_LIST_HEAD(®ion->list);
+ region->start = start;
+ region->length = length;
+ region->prot = prot;
+ region->type = type;
+ return region;
+}
+
+/* Request that a device is direct mapped by the IOMMU */
+int iommu_request_dm_for_dev(struct device *dev)
+{
+ struct iommu_domain *dm_domain;
+ struct iommu_group *group;
+ int ret;
+
+ /* Device must already be in a group before calling this function */
+ group = iommu_group_get_for_dev(dev);
+ if (IS_ERR(group))
+ return PTR_ERR(group);
+
+ mutex_lock(&group->mutex);
+
+ /* Check if the default domain is already direct mapped */
+ ret = 0;
+ if (group->default_domain &&
+ group->default_domain->type == IOMMU_DOMAIN_IDENTITY)
+ goto out;
+
+ /* Don't change mappings of existing devices */
+ ret = -EBUSY;
+ if (iommu_group_device_count(group) != 1)
+ goto out;
+
+ /* Allocate a direct mapped domain */
+ ret = -ENOMEM;
+ dm_domain = __iommu_domain_alloc(dev->bus, IOMMU_DOMAIN_IDENTITY);
+ if (!dm_domain)
+ goto out;
+
+ /* Attach the device to the domain */
+ ret = __iommu_attach_group(dm_domain, group);
+ if (ret) {
+ iommu_domain_free(dm_domain);
+ goto out;
+ }
+
+ /* Make the direct mapped domain the default for this group */
+ if (group->default_domain)
+ iommu_domain_free(group->default_domain);
+ group->default_domain = dm_domain;
+
+ pr_info("Using direct mapping for device %s\n", dev_name(dev));
+
+ ret = 0;
+out:
+ mutex_unlock(&group->mutex);
+ iommu_group_put(group);
+
+ return ret;
+}
+
+const struct iommu_ops *iommu_ops_from_fwnode(struct fwnode_handle *fwnode)
+{
+ const struct iommu_ops *ops = NULL;
+ struct iommu_device *iommu;
+
+ spin_lock(&iommu_device_lock);
+ list_for_each_entry(iommu, &iommu_device_list, list)
+ if (iommu->fwnode == fwnode) {
+ ops = iommu->ops;
+ break;
+ }
+ spin_unlock(&iommu_device_lock);
+ return ops;
+}
+
+int iommu_fwspec_init(struct device *dev, struct fwnode_handle *iommu_fwnode,
+ const struct iommu_ops *ops)
+{
+ struct iommu_fwspec *fwspec = dev->iommu_fwspec;
+
+ if (fwspec)
+ return ops == fwspec->ops ? 0 : -EINVAL;
+
+ fwspec = kzalloc(sizeof(*fwspec), GFP_KERNEL);
+ if (!fwspec)
+ return -ENOMEM;
+
+ of_node_get(to_of_node(iommu_fwnode));
+ fwspec->iommu_fwnode = iommu_fwnode;
+ fwspec->ops = ops;
+ dev->iommu_fwspec = fwspec;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(iommu_fwspec_init);
+
+void iommu_fwspec_free(struct device *dev)
+{
+ struct iommu_fwspec *fwspec = dev->iommu_fwspec;
+
+ if (fwspec) {
+ fwnode_handle_put(fwspec->iommu_fwnode);
+ kfree(fwspec);
+ dev->iommu_fwspec = NULL;
+ }
+}
+EXPORT_SYMBOL_GPL(iommu_fwspec_free);
+
+int iommu_fwspec_add_ids(struct device *dev, u32 *ids, int num_ids)
+{
+ struct iommu_fwspec *fwspec = dev->iommu_fwspec;
+ size_t size;
+ int i;
+
+ if (!fwspec)
+ return -EINVAL;
+
+ size = offsetof(struct iommu_fwspec, ids[fwspec->num_ids + num_ids]);
+ if (size > sizeof(*fwspec)) {
+ fwspec = krealloc(dev->iommu_fwspec, size, GFP_KERNEL);
+ if (!fwspec)
+ return -ENOMEM;
+
+ dev->iommu_fwspec = fwspec;
+ }
+
+ for (i = 0; i < num_ids; i++)
+ fwspec->ids[fwspec->num_ids + i] = ids[i];
+
+ fwspec->num_ids += num_ids;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(iommu_fwspec_add_ids);